An eruption at the intracaldera cone is likely underway today as determined from satellite observation of elevated surface temperatures this morning at 13:25 UTC (05:25 AKDT), prompting AVO to raise the Aviation Color Code and Volcano Alert Level to ORANGE/WATCH. Seismic tremor continues and is indicative of low-level effusive activity and small explosions. No ash plumes have been observed this morning although clouds have obscured web camera views of the summit. Any low-level plume produced would drift to the northwest based on predicted wind trajectories.

AVO has been monitoring Veniaminof closely since elevated levels of seismicity became persistent on June 8. Steam plumes issuing from the intracaldera cone have been observed in web camera views since then, but so far no ash emissions have been confirmed.

Recent eruptions of Veniaminof Volcano have all occurred from vents located on the intracaldera cone and were characterized by brief bursts of ash emission and small explosions. Ash plumes associated with this type of activity are typically diffuse and generally do not reach more than 20,000 feet above sea level. Ash fallout is typically limited to the flanks of the volcano. Minor emissions of steam and ash may persist for for weeks to months. The last episode of more energetic activity occurred in 1993-94 when an ash plume rose to about 18,000 feet above sea level and small lava flows poured onto glacier ice around the intracaldera cone. An eruption in 1983-84 produced an ash plume that reached about 25,000 feet above sea level.

Persistent elevated surface temperatures consistent with lava effusion were observed over the past day in satellite images. Web camera views have been cloudy. Wind trajectories suggest that low-level plumes would traverse to the northeast and southeast; however, no plumes have been observed in recent satellite images.

The technical problems that temporarily disabled the real-time seismic data feeds from Pavlof Volcano yesterday have been resolved and the data stream was restored within a few hours.

Low-level clouds obscured web camera views of the volcano in the past 24 hours. No elevated surface temperatures were observed in satellite images. We have received no other reports of activity at the volcano.

Sudden explosions of blocks and ash are still possible with little or no warning. Ash clouds, if produced, could exceed 20,000 feet above sea level. If a large ash-producing event occurs, nearby seismic, infrasound, or volcanic lightning networks should alert AVO staff quickly. However, for some events, a delay of several hours is possible. Cleveland volcano does not have a local seismic network and is monitored using only distant seismic and infrasound instruments and satellite data.

VOLCANO INFORMATION ON THE INTERNET: http://www.avo.alaska.eduRECORDING ON THE STATUS OF ALASKA'S VOLCANOES (907) 786-7478

The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.